I realize that's not what most people have in mind when they ask for profit sharing. They want to be a part of an already successful operation, and take no risks. And that's precisely what I've been talking about. The process of building a successful business is given little thought, as if they grow on the trees or are being brought to Earth by meteors.
Then there's that thing with businesses statistically being just slightly more often in black than in red. Would your profit sharing scheme involve absorbing the losses as well? How many takers you think it will have? If not them, who will get to absorb the losses, potentially reinvest to weather through rough times etc? The expense would be not negligible, on the order with the profits.
When the firm spends more than it produces, it needs access to capital. This can be in the form of savings, credit, or new investment. Small new businesses are routinely launched through loans. Credit institutions are quite used to absorbing losses.
A worker-owned coop can also take investment from external capitalists. It would just be in the form of a profit-sharing contract rather than equity with voting rights.
> Credit institutions are quite used to absorbing losses.
They are also quite good at taking the profits on their investments. If a bank bails you out, it wants to take its pound of flesh. You essentially arrived at status quo.